In many industries, articles supported on hooked members are conveyed on an assembly line. For example, in laundry and dry cleaning facilities, garments supported on hangers are often loaded onto automated conveyors, such as those described in U.S. Pat. No. 5,220,511 to Speckhart et al., expressly incorporated herein by reference. In large laundry and dry cleaning facilities, the garments are loaded onto a sorting conveyor in an unsorted order. There are typically several drop-off stations located at various points along the sorting conveyor. The garments are sorted by moving the sorting conveyor and unloading each garment into a respective drop-off station in a predetermined order. The sorted garments at the drop-off stations are then loaded into trucks for delivery to customers. Exemplary sorting systems are described in U.S. Pat. No. 5,299,134 and U.S. Pat. No. 5,220,511 (both issued to Speckhart et al.), expressly incorporated herein by reference.
In order to sort the garments on the sorting conveyor, it is necessary to first identify (for example, by customer number) each garment in the unsorted sequence of garments. Each garment typically includes a label displaying the necessary identifying information. If the garment has a collar, the label is often located on the interior surface of the collar. If the garment has a waistline, the label is typically located on an exterior surface of the waistline.
In conveying systems, once each hooked member is placed on the conveying line, the hooked member, and the article supported thereon, is typically oriented in a fixed position. The hooked members are often placed in close proximity to neighboring hooked members on the conveying line in order to maximize the usage of space on the conveyor. For example, garment hangers are typically oriented such that the body of each hanger, i.e., the portion of the hanger supporting the garment, is orthogonal to the conveying line. Thus, it is typically not possible to rotate (relative to the conveying line) any one of the hangers, or the article supported thereon, while it is being conveyed. Accordingly, the identification information displayed on a garment's label is usually read by a human operator, and entered into a computer along with information related to the position of the hanger relative to other hangers in the conveying line.
One solution to this problem is proposed in U.S. Pat. No. 5,377,814 issued to Smith et al., expressly incorporated herein by reference. In the system described in the Smith '814 patent, each garment hanger is removably mounted on an individual transport carrier.
Each transport carrier has a unique bar code displayed thereon. The transport carrier bar code is initially correlated with customer information displayed on the garment. The transport carrier bar code is then read as it progresses through the sorting system, and compared with a computer data base of garment information to determine the sorting route. However, this system requires special hardware, in particular, individual transport carriers with bar codes. Accordingly, older conveyor systems cannot be easily retrofitted to implement such a solution.
In another type of system, a transponder mounted in a holder is detachably supported to each hanger supporting a garment. The transponder transmits a unique identification signal (e.g., a unique RF signal) in response to an interrogation signal from a conveyor system. Accordingly, each unique identification signal is initially correlated with customer information displayed on the garment. Each transponder is then interrogated as it progresses through the sorting system, and compared with a computer data base of garment information to determine the sorting route. While such existing conveyor systems may be retrofitted to incorporate these transponders, each transponder is relatively expensive.